Commit cf056a43 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

init: improve the name_to_dev_t interface 



name_to_dev_t has a very misleading name, that doesn't make clear
it should only be used by the early init code, and also has a bad
calling convention that doesn't allow returning different kinds of
errors.  Rename it to early_lookup_bdev to make the use case clear,
and return an errno, where -EINVAL means the string could not be
parsed, and -ENODEV means it the string was valid, but there was
no device found for it.

Also stub out the whole call for !CONFIG_BLOCK as all the non-block
root cases are always covered in the caller.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230531125535.676098-14-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent c0c1a7dc

Documentation/admin-guide/kernel-parameters.txt

+2 −2
Original line number Diff line number Diff line
@@ -5453,8 +5453,8 @@ 


	root=		[KNL] Root filesystem

			Usually this a a block device specifier of some kind,

			see the name_to_dev_t comment in init/do_mounts.c for

			details.

			see the early_lookup_bdev comment in init/do_mounts.c

			for details.

			Alternatively this can be "ram" for the legacy initial

			ramdisk, "nfs" and "cifs" for root on a network file

			system, or "mtd" and "ubi" for mounting from raw flash.

drivers/md/dm-table.c

+3 −2
Original line number Diff line number Diff line
@@ -330,8 +330,9 @@ dev_t dm_get_dev_t(const char *path) 
{

	dev_t dev;



	if (lookup_bdev(path, &dev))

		dev = name_to_dev_t(path);

	if (lookup_bdev(path, &dev) &&

	    early_lookup_bdev(path, &dev))

		return 0;

	return dev;

}

EXPORT_SYMBOL_GPL(dm_get_dev_t);

drivers/md/md-autodetect.c

+2 −1
Original line number Diff line number Diff line
@@ -147,7 +147,8 @@ static void __init md_setup_drive(struct md_setup_args *args) 
		if (p)

			*p++ = 0;



		dev = name_to_dev_t(devname);

		if (early_lookup_bdev(devname, &dev))

			dev = 0;

		if (strncmp(devname, "/dev/", 5) == 0)

			devname += 5;

		snprintf(comp_name, 63, "/dev/%s", devname);

drivers/mtd/devices/block2mtd.c

+1 −2
Original line number Diff line number Diff line
@@ -254,8 +254,7 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size, 
			msleep(1000);

		wait_for_device_probe();



		devt = name_to_dev_t(devname);

		if (!devt)

		if (early_lookup_bdev(devname, &devt))

			continue;

		bdev = blkdev_get_by_dev(devt, mode, dev, NULL);

	}

fs/pstore/blk.c

+2 −2
Original line number Diff line number Diff line
@@ -263,9 +263,9 @@ static __init const char *early_boot_devpath(const char *initial_devname) 
	 * same scheme to find the device that we use for mounting

	 * the root file system.

	 */

	dev_t dev = name_to_dev_t(initial_devname);

	dev_t dev;



	if (!dev) {

	if (early_lookup_bdev(initial_devname, &dev)) {

		pr_err("failed to resolve '%s'!\n", initial_devname);

		return initial_devname;

	}